Prince George's County police identified the Newark girls as Ariana Decree, 9, and her younger sister Ajayah Decree, 6, of Palmer Street.
When the mother, Andrena Kelley, returned home from work early Friday morning, she discovered the girls in their beds, suffering from what appeared to be stab wounds.
"This is one of the most hard scenes that our officers arrived on", police department spokeswoman Jennifer Donelan said.
Williams has been charged with three counts of first and second-degree murder and other related charges.More news: NSAC Defend Mayweather McGregor Gloves Ruling
Police previously said an adult family member found the dead children - all with trauma to their bodies - inside the home. Paramedics were called, but all three girls were pronounced dead.
"We are now in the midst of a major investigation into what happened to these children", Donelan said, adding that it was one of the "most hard scenes" the department's officers have ever seen.
Antonio Williams, 24, of Clinton, Md. was arrested Friday, but no further details of the arrest has been released at this time.
Investigators are interviewing "a number" of people for the investigation, police said.More news: Karnataka gets Indira Canteens: Breakfast for Rs 5, lunch for Rs 10
"We all feel this loss", Velez said.
Prince George's County Police have reported a capture in the slaughtering of three young ladies whose bodies were found at a home in Clinton.
That work is being done working together with the workplace of State's Attorney Angela Alsobrooks, who accepted the open door to talk for the benefit of province inhabitants, saying, "We are completely shattered and we are so totally crushed".
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